Known from WO 00/02775 A is a high-lift flap on a wing for large aircraft which has jags extending in the direction of flow in order to reduce the vortex trail of the wing.
EP 1 149 761 A1 describes vortex generators which are configured as elongated elements on a profile surface of a control surface.
U.S. Pat. No. 6,283,406 B1 discloses a rotor blade for helicopters which, for influencing vortex, has air intake passages for admitting air on a first longitudinal side and air output passages for expelling air on a second longitudinal side located opposite to said first longitudinal side.
EP 0 689 990 A1 describes a rotor blade for helicopters which has outlet openings and a device for ejecting air through these outlet openings.
Modern passenger aircraft use so-called high-lift aids during the takeoff and landing phase to produce the necessary lift at low speeds. Along with the landing gear, these aircraft components, divided into leading-edge flaps and landing flaps, are the main generators of aerodynamic noise in passenger aircraft. During the landing approach when the engines are strongly throttled, this noise can reach the same order of magnitude as that of the engines.
Comprehensive research programmes, both in the USA and in Europe, have shown that substantially two source regions on the high-lift aids are responsible for generating this noise: the rear side of the leading-edge flap and the lateral edge of the landing flap. The generation of the noise in the last-mentioned source region can be attributed to the lateral edge vortex produced by the flow around the lateral edge. This flow is caused by the pressure difference between the upper and lower side of the landing flap. As a result of the relatively high deflection angle of the landing flap, vortex shedding takes place both at the upper and at the lower edge of the lateral surface, and these combine to form a large vortex after a certain running length. The interaction of this vortex with the surface of the landing flap then leads to the formation of noise.
A device for reducing the aerodynamically induced noise at the lateral edge of a control flap, in particular of a high-lift flap of an aircraft is known from DE 100 20 177 A1, wherein a vortex generator is formed by a number of elements extending in the wing span direction on the lateral edge of the control flap, between which air flowing past the control flaps flows. The elements extending in the wing span direction are configured as elongated and are provided in the form of brush-like arrangements which run over one or more sections of the profile depth of the control flap.
Also known from U.S. Pat. No. 3,596,854 is a vortex generator which comprises a tubular element running along the lateral edge of the control flap having an orifice which opens towards the rear side of the control flap through which the compressed air collected on the overpressure side of the high-lift flap is released. The direction of rotation of the vortex can be selected in the sense of an enlargement or a reduction in the lift force of the high-lift flap.